Pulp beater



March 1951 w. N. SHERWOOD PULP BEATER 2 Sheeis-Sheec 1 Filed Oct. 20,1945 Patented Mar. 27, 1951 UNITED STATES PATENT OFFICE PULP BEATERWalter N. Sherwood, Eagle Bridge, -N. Y. Application October 20, 1945,Serial No. 623.474

.6 .Claims.

Myinvention relate s to papermaking and-more particularly to an improvedpulp beater of the type disclosed in my Patent No. 2,078,030grantedApril 20, 1937.

One of the objects of my invention is'to .provide a vat or tub of animproved shape whereby the flow of stockfrom the rear to the front ofthe roll is greatlyfacilitated. Another object is toprovide-a newandimproved type of bed plate which cooperates directly with the rollthroughout adistance-approximating the diameter of. the roll and inwhich no bed plate boxesarenecessary. Anotherobject is-to provideanimproved type otguide.plateattherear of the bed plate in.-whichtheupperv surface. thereof conformsapproximately to the trajectory ofthe vstoclrand servesto guide the thrown stock upand rearwardly,- whilethe lower surface thereof, in cooperationwith the:bridge whichsupportsthebed plate, offers asmooth', streamlined guide for. confining,atzthe top thereof, the mass ofstock moving toward the front of the.beater. Another objectis to'provide, invconnectionswith thellastmentioned object, -a tub having the :inside surfaces ofthe ,ends andbottom thereof so .correlatedrasrto form :asubstantially smoothly curvedor streamlined path orpassageway for the mass of stock movingaf-rom therearto the front of the ;-roll, .-whereby continuous movement of .theentire'stock' mass is assured under the potential head-built up by theaction of the roll in. the rear end of thetub. ;Ano ther objectistoprovide a heater of such design thatthe stock,;before it flowstcothe011, issubiecte toasur ing, r011- ingandtumb1ing actionby passing itover a am avin anadiu tabl cre t wh reby atheru git tion an .mi th r-eoi a tain r o h ob ect i t provid m ns-fo tr pp nso en n n o n a theockat th rea o h t a d i j fro o rrc an more particularly toprovide ameans whereby theaction'of the roll will induce afiow of cooling airaround the front .of the roll, and means whereby cooling air wi-llbeentrapped between theloop ofst c throw up l h th o an the mass of stocktherebelow in the tub.

other objectis to provide a; lighter beam having me n f ra i tin th smeatea h en thereof. whereby the surface-of the rollmay .be. madeprecisely. concentricwith the bed plate. ,Another object is .to providea roll .and. bed plate combination. in which the stock is admitted.between the roll. and the bed plate .and .is -.discharged from-betweenthe roll and the :bed .plate at substantially .sthe same .elevation, and.preferably, approximately half way between the roll axis and the bottomcenter of .the roll surface. Another object is to provide .a targetagainst which the stock will be thrown fromthe rolland which willfurther facilitate the'hydra'tion .thereof and the breaking up ofbundles of fiber there,- in. Another object is to provide such anarrange'ment of fiylbars in the roll and bars in the bed plate as willeffect analternatebrushirig and combing of the fibers. A further objectis to provide a heater having .aIbeater roll of ..comparativelyismalldiameter which may be operated at comparatively high speed and which isso correlated with the bed plate .thatIthe number of inch .euts perminute may very wellvbelof an order in excess of halfabillion.

With these objects in view my invention includes the .novel elementsandthecombinations and arrangements thereof described below .and

illustrated in the accompanying drawings ,in

which- Fig. 1 is a moreor less diagrammatic sectional elevationview of.my-beater;

Fig. 2 is .aperspective view of .a flexiblegate or dam regulating thedepth of stock which'is fed toa second gate immediatelyin front ofthe'roll;

Fig. -3.is anelevation viewpartiallyinsection with portions brokenawayshowing a lighter beam of my beater with ameans for adjusting eachend thereof;

Fig. 4 is a section of Fig. 3 in-the planeATA;

Fig. 5 is .a.-fragmentary.end elevation viewof a portion of theperiphery of the beater roll;

Fig. 6 is an .end elevation viewof oneof the sections of thebed plate;

Fig. 'Tis a ,diagrammaticoend .view ofthe .bed plate for the purpose ofdescribing thepreferred arrangement of the bars. therein; and

Fig.8 is a fragmentary section of Fig.1 in the plane 8--'8.

Referring, first to Figs. 1 and -2 My beater comprises .atub Lhavingabottom 2 and downwardly and inwardly inclined ends 3 and .4 whicharedesignedtofacilitate theiiow of stock from. the. rear end to the frontend of thetub. Suspended in the. central portion of the tub andextending from side topside thereof is a bridge 5 composed ofmetalnplates '6 and timbers]. Both the upper suriaceand the lowersurface of the bridge are smooth, cylinders; the upper surfacesupporting the bedplate :1 directly thereon, and the undersurface ,ofthe bridge being,spacedsubstantially from. the bottom of the,tubtoprovidefor the flow -of...stock 3 therebelow. 8 is the roll of alength which is understood to extend from side to side of the tub and towhich are secured a plurality of fly bars 9 shown in detail in Fig. 5.At the rear of the roll is a guide In, functioning as a backfall, whichextends from side to side of the tub and the upper surface of which isslightly convex, as shown, to form a guide for the stock thrown from theroll. The upper surface of the guide In is made convex to conformapproximately to the trajectory or natural curvature of the bottom ofthe stream of stock as it is thrown from the roll, and hence thecurvature will depend somewhat on the speed at which the roll isdesigned to operate. In the top rear portion of the tub and with atleast the upper portion thereof disposed in the path of the stock thrownby the roll is a screen lining ll formed of angularly disposed sectionsdesigned to form a target against which the stock is directed and whichfacilitates the hydration thereof and promotes the disintegration ofsmall bundles of fiber as they impinge against it. Preferably thesescreens vary from coarse at the top to fine at the bottom. The bottomportion l2 of the stock guide at the rear of the roll is preferably ofsheet metal forming a substantially plane surface which is disposedtangent, at [3, to the bottom of the bridge 5, and which forms a meanscooperating with the interior surfaces of the tub end and sides at therear of the roll, and with said bridge, to form a stock passage ofapproximately uniform cross section throughout this position of the tuband within which the lateral flow of stock is restricted so that it mustflow substantially downwardly. I4 is a truss or brace which extends fromside to side of the tub. I5 is an air opening in the side of the tub andit is to be understood that there is an oppositely disposed opening ISin the other side of the tub. Extending between the bottoms of theseopenings is a guard I6. Thus, air will be induced by the stock which isprojected from the roll at high velocity beneath the guard I6 to flowinto the tub through the openings l5 as shown by the arrow I1. jacentthe screens l l and in the upper rear sides of the tub are oppositelydisposed air openings l8 which, however, are positioned below the pathof the stock projected from the rear of the roll so that cooling air mayflow freely into the tub just underneath the loop of projected stock.

The sides of the tub, above the roll, are provided with a plurality ofair openings I9, and disposed between these openings and the top of theroll are a number of curved baflles which extend from side to side ofthe tub. The adjacent ends of these baffles overlie each other to formnozzle-like passages 2| and 22 through which air is induced to flow, bythe action of the roll, downwardly into the zone where the stock meetsthe roll at the front thereof.

23 is a suspended platform which extends from side to side of the tuband which forms the bottom of a trough or channel through which stockflows down grade directly to the roll. 24 is an adjustable gate which isdisposed to regulate the depth of the stock in a zone immediatelyadjacent the front of the roll and 24 is a spatter board pivotallymounted at 62, and which may be rotated and set in any position by meansof the crank 63. Where the stock flows on to the platform 23 I provide aflexible metal gate or dam 25, shown in detail in Fig. 2, and whichcomprises a pipe 26 at the free end of the gate and around which themetal is wrapped, as

shown. This gate slides under a strap 2! overlying the platform 23, andthe cover 23 of the tub which overhangs the crest of the dam 25 ishinged at 29, whereby to provide a hand hole for adjusting the positionof the gate or dam 25 to control the stock flowing thereover. In orderto secure the gate 25 in adjusted position the opposite sides of the tubmay be provided with a plurality of small holes (not shown) throughwhich a bolt or pin 54, or the like, may be thrust into the adjacentends of the pipe 26, as shown in Fig. 8. 3B is a manhole, while 3|represents in a purely diagrammatic way, a washer which may be loweredinto the path of the stock flowing to the roll in order to regulate theconcentration thereof.

Due to the comparatively narrow bed plates ordinarily used in beaters,or to the positions in which they are disposed with respect to thebottom center of the cooperating roll, the usual lighter beams uponwhich the bearings for the roll are supported are pivoted at one endonly and are provided with means at the other end for moving the beamsabout their pivotal mountings to regulate the distance between the rolland the bed plate.

Due to the width of my bed plate, which preferably approximates thediameter of the roll, this would be an undesirable arrangement in mybeater and I, therefore, provide means whereby both ends of the lighterbeams upon which the roll bearings are supported may be adjusted so thatthe roll may be maintained approximately concentric with the bed plateat least when the surface of the roll is not far above the bed plate.Thus, in Figs. 3 and 4, 32 is a lighter beam carrying the bearing 33 forthe roll shaft 34. Secured to the side of the tub I adjacent one end ofeach lighter beam is a stud 35. Mounted to turn on the stud 35 is asleeve 36 which is secured in place against a shoulder 31 on the stud bymeans of the nut 38. The lighter beam 32 is provided with a cut-outportion 39 through which the stud 35 projects, and directly above andbelow the cutout portion 39 the beam is threaded to receive the screws40 and 4| which have end portions of reduced diameter, as shown at 42,which are received in diametrically disposed openings in the sleeve 36.The entire load of the lighter beam at this end is carried by the upperscrew 40, and by turning down on this screw, or by letting off on it,this end ofthe lighter beam may be raised or lowered, respectively. Thelower screw 4! is merely for holding the end of the lighter beam firmlyin adjusted position. At the other end, the lighter beam is providedwith a threaded passage adapted to receive the adjusting screw 43, thelower end 44 of which is received in the cuplike recess 45 in the fixedsupport 46. Screw 43 is provided with a hand wheel 41 and hand grip 48by which it may be turned.

There is considerable diversity of opinion among beater manufacturers asto the proper type, size and arrangement of the bars both in the rolland in the bed plate in order to attain the best results.

While I do not wish to limit myself to any particular size of roll Ihave found in actual practice that, with a 48 roll and a 48" bed plate,made according to my invention, the stock can be broken down intoindividual fibers without damaging the fibers and thereby withoutreducing the strength of the paper by arranging the bars about asdescribed below. Thus, instead of hav-. ing only one type of bar in theroll the results. are

very i'nuch better if comparatively thick bars are alternated withcomparatively thin bars, as shown in Fig. 5. By so arranging the barsthe fibers are -subje'cted alternately to a combing and brushing action.I prefer to use composite bars comprising stub bars 49,- whieh aresecured to the roll in the usual manner by means of the ring 50, andwhich are capped by working bars secured thereto by rivets or bolts 5|so that renewal of the working bars, when worn, is facilitated.

My preferred bar arrangement for a 48" roll would consist of 62 stubroll bars 49. All of the caps or working edges of the stub bars wouldcomprise two outside bars 52 between which the other working bars aresecured by means of rivets 53. Everyother one of the caps would comprisethree bars 54 1%? in thickness and spaced from each other and from theside of the bars '52 by 1% wood fillers 55. The stub bars alternatingwith the bars just described have caps or working edges comprising, inaddition to the side bars 52, asin- 'gle bar 56 which is 1- 5" inthickness and which is spaced from the side bars 52 by 1 5'" fillers 51.Thus every other bar of the rollfunctions as a comb, and the other barsas brushes.

I prefer to form my bed plate in twelve separate sections showndiagrammatically in l ig. 7. Since for a 48 roll the width of the bedplate, according to my invention, should preferably approximate thediameter of the roll, each of the sections in the bed plate would have athickness, measured circumferentially of the face thereof, ofapproximately 4". The width or de th of the bars may be only from 1 toBinches, depending somewhat on the diameter of the roll; the greaterdepth or width being used with the larger rolls.

In the following table 1 have set forth my preferred size andarrangement of the bars in the bed plate; the sections being asindicated in Fig.

The first bar 58 and the last bar 59 in each section should be thickenough to permit the heads of the rivets Bil which secure the barstogether to be countersunk.

Squeezing and bruising the fibers is the best means for softening andloosening the outer fiber layers Without damaging them and my roll andbed plate are designed to subject the fibers precisely to thistreatment. Furthermore, a bed plate approximating in width the diameterof the roll in accordance with my invention permits the use of a widergap between the roll and the plate than is the case in other beaters.Because of this fact cutting of the fibers is not only prevented but agreat saving in power is also effected.

By using a multiplicity of comparatively thin bars with very thinfillers between them the fibers cannot refuse to take treatment by slip=ping and sliding into the wide spaces which 6 exist in heaters whereonly a comparatively few bed plate bars are employed.

By utilizing the space between the bed plate and the bottom of the tubas a stock return passage the mid-feather is entirely eliminated and aconsiderable saving in fio'or space is effected because the tub can bemade narrower but higher than the present common type of beater.

By inducing a flow of air into the stock both in front of the roll andat the rear of the roll the stock is maintained cool and overheating isprevented.

In the specific embodiment of my invention described above in connectionwith a 48" roll it is possible to operate the roll at comparatively highspeed. That is to say, between 200 and 300 R. P. M. (preferably about250 R. P. M.). This projects the stock from the roll towards the targetat high velocity with a comparatively fiat trajectory so that the impactwith the screen target is particularly effective in facilitating thehydration of the stock and the breaking up of small bundles of fibertherein.

It will be noted that the shape of my beater is such, and the meansforming the top and bottom of the stock passage in that portion thereofat the rear of the roll, are so correlated that lateral spreading orflowing of the stock in the zone where it is projected from the roll isrestricted and flow thereof is substantially downward. Thus, a verysubstantial head of stock can be built up in that portion of the tubbehind the roll which functions to drive or force the stock underneaththe bed plate bridge, towards the front end of the tub and upwardly overthe adjustable dam 25. In other words, the cross-sectional area of thatportion of the stock passage extending from the top of the guide In tothe bottom of the bridge 5 is restricted and approximately constant sothat it functions in a manner quite analogous to a standpipe which ismaintained substantially full at all times by the roll action, and thusprovides a substantial and constant head or pressure on the stock in thetub which creates not only a rapid, horizontal flow of stock through thetub but also upwardly at the opposite end thereof.

Since the top of the tub at the front end thereof substantiallyoverhangs the edge or crest of the adjustable dam 25, a passage oflimited but variable cross-sectional area is here provided through whichthe stock must pass on its way to the roll. By adjusting the height ofthe dam crest the velocity and action of the stock can be controlled atthis point either to cause the stock merely to surge over the darn or toroll and tumble 'thereover in a manner to provide a very thorough mixingthereof.

Furthermore, it will be apparent from Fig. 1, that the cross section ofthe stock passage between the platform '23 and the inclined end 4 of thetub is gradually and quite smoothly reduced in size as itapproaches thegate 25 so that a substantially uniform flow of stock is maintainedthroughout each cross section of the passage in this zone. In otherwords, there are no portions of the stock passage in this zone, or, forthat matter, in any other zone thereof, in which a mass of stock canbecome lodged or settled and refuse to circulate. Moreover, this gradualreduction in cross section of the stock passage as it approaches therestricted passage at the gate 24', makes the passage through the gate25 function as a sort of nozzle through which stock surges underpressure of the head thereon.v

It is well known that a vertical pipe of small cross-sectional areaconnected to a closed container and filled with liquid or other flowablematerial produces just as much head or pressure on the material in thecontainer as a very large pipe under the same conditions. It is thisprinciple which I employ in providing a driving head or force for thestock in my beater. r

While I have described my invention in its preferred embodiment it is tobe understood that the words which I have used are words of descriptionrather than of limitation and that changes within the purview of theappended claims may be made without departing from the true scope andspirit of my invention.

What I claim is:

1. In a pulp beater, the combination with a tub, of a bed plateextending from side to side of said tub and suspended above the bottomthereof to provide a passage for the fiow of stock through said tubbelow said plate, a roll adapted to be rotated at comparatively highspeed cooperating with said bed plate throughout a distanceapproximating its diameter; said bed plate being approximatelysymmetrically disposed with respect to a vertical plane through the axisof said roll, whereby stock will be projected from said roll at highvelocity, at a substantial angle to the horizontal, and to a substantialheight to maintain a high level of stock in said tub behind said roll; aplatform fixedly suspended above the bottom of said tub and forming withthe sides thereof a trough having its bottom extending from a zoneclosely adjacent both the end and top of said tub in front of said rolldownwardly to said bed plate for the flow of stock therethrough to thedescending side of said roll; a cover on said tub extending from the endthereof in front of said roll to a zone closely adjacent but above thelevel of the bottom of said trough at the entrance thereto and formingwith the sides and end of said tub and the bottom of said trough acompletely laterally enclosed passage of restricted cross-sectional areafor the flow of stock therethrough under pressure into said trough;whereby a rolling and tumbling thereof will take place as it isdischarged into said trough, and a thorough mixing thereof Will befacilitated.

2. In a pulp beater, the combination with a tub, of a bed plateextending from side to side of said tub and suspended above the bottomthereof to provide a passage for the flow of stock through said tubbelow said plate, a roll adapted to be rotated at comparatively highspeed cooperating with said bed plate throughout a distanceapproximating its diameter; said bed plate being approximatelysymmetrically disposed with respect to a vertical plane through the axisof said roll, whereby stock will be projected from said roll at highvelocity, at a substantial angle to the horizontal, and to a substantialheight to maintain a high level of stock in said tub behind said roll; aplatform fixedly suspended above the bottom of said tub and forming withthe sides thereof a trough having its bottom extending from a zoneclosely adjacent the end of said tub in front of said roll downwardly tosaid bed plate on the descending side of said roll for the flow of stockto said roll, a gate slidably mounted on the bottom of said trough atthe entrance thereto and adapted to be drawn out towards the adjacentend of said tub to form an extension of said bottom and, with the endand sides of said tub, a restricted passage of adjustablecross-sectional area for the flow of stock therethrough under pressureinto said trough.

3. A pulp beater comprising an elongated tub having side walls, endwalls and a bottom; said end walls and said bottom merging substantiallysmoothly into each other; a roll of a length substantially equal to thewidth of said tub rotatably mounted therein; a bed plate cooperatingwith said roll throughout a distance approximating the diameter of saidroll, whereby stock will be initially projected from said roll at asubstantial angle to the horizontal and to a comparatively highelevation in said tub behind said roll; means above the bottom of saidtub for the free flow of stock therebetween for supporting said bedplate; a backfall extending upwardly from said bed plate and said bedplate supporting means and having the bottom thereof above andsubstantially spaced from the bottom of said tub;

\ a platform fixedly suspended above the bottom of said tub and formingwith the sides of said tub a downwardly inclined trough extending from azone closely adjacent the end of said tub in front of said roll at anelevation only slightly above the end of said bed plate on thedescending side of said roll to said bed plate; a cover on said tubmerging comparatively smoothly with the end wall of said tub in front ofsaid roll and extending to a zone closely adjacent but above theadjacent end of said trough and forming with said platform and the sidesof said tub an entrance to said trough of restricted cross-sectionalarea for the flow of stock therethrough under pressure, and to effect arolling, tumbling and mixing of said stock as it enters said trough; thebottoms of said backfall, said bed plate supporting means, and saidplatform forming with the sides, bottom and ends of said tub asubstantially streamlined stock passage throughout, and of substantiallyuniform cross-sectional area throughout, except in the zone approachingthe entrance to said trough, where the cross-sectional area of saidpassage is gradually and substantially uniformly reduced to a minimum atsaid entrance.

4. A pulp beater comprising a tub, a bed plate extending from side toside of said tub and sus pended above the bottom thereof to provide forthe flow of stock through said tub therebelow, a roll cooperating withsaid bed plate throughout a distance approximating the diameter of saidroll and adapted to be rotated at comparatively high peripheral speed,whereby stock will be projected by said roll, as it leaves said bedplate, at substantial velocity and at a substantial angle to thehorizontal to maintain stock in said tub at a comparatively highelevation behind said roll; means, including the sides of said tub,forming a fixed, elongated, downwardly inclined trough extending from azone closely adjacent the end and top of said tub in front of said rollto said bed plate on the descending side of said roll; and a cover onsaid tub extending from the end thereof to a zone closely adjacent butabove the level of the bottom of said trough at the entrance thereto forguiding and maintaining said stock under pressure substantially until itis discharged into said trough; whereby a rolling and tumbling of saidstock is produced as it is discharged into said trough, and a thoroughmixing thereof takes place.

5. A pulp beater comprising a tub, a bed plate extending from side toside of said tub and suspended above the bottom thereof to provide forthe flow of stock through said tub therebelow, a roll cooperating withsaid bed plate throughout a distance approximating the diameter of saidroll and adapted to be rotated at comparatively high peripheral speed,whereby stock will be projected by said roll, as it leaves said bedplate, at substantial velocity and at a substantial angle to thehorizontal to maintain stock in said tub at a comparatively highelevation behind said roll; means, including the sides of said tub,forming a fixed, elongated, downwardly inclined trough extending from azone closely adjacent the end and top of said tub in front of said rollto said bed plate on the descending side of said roll; a cover on saidtub extending from the end thereof to a zone closely adjacent but abovethe level of the bottom of said trough at the entrance thereto forguiding and maintaining said stock under pressure substantially until itis discharged into said trough; whereby a rolling and tumbling of saidstock is produced as it is discharged into said trough, and a thoroughmixing thereof takes place; a gate, and a slidable mounting therefor atthe entrance to said trough adapting said gate to be pulled out to forman extension of the bottom of said trough cooperating with the sides,

end, and cover of said tub to form an adjustable the elevation of theextended bottom of said trough at the entrance thereto and thecrosssectional area of the stock passage at said entrance; together withmeans for securing said gate in flexed condition.

WALTER N. SHERWOOD.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 662,726 Jones Nov. 27, 19001,144,666 North June 29, 1915 1,185,926 North June 6, 1916 1,679,056Shlick July 31, 1928 1,716,407 Wood June 11, 1929 1,838,875 Shartle Dec.29, 1931 1,863,808 Sherwood June 21, 1932 2,078,030 Sherwood Apr. 20,1937 2,148,448 Edwards Feb. 28, 1939 FOREIGN PATENTS Number Country Date17,483 7 Great Britain 1890 209,693 Great Britain June 17, 1924 355,635Great Britain Aug. 27, 1931 632,521 France Apr. 7, 1927

